Communication apparatus, communication method, and storage medium

ABSTRACT

Network slice information indicating a characteristic of a wireless network to be provided by a base station is acquired, and whether the base station provides a predetermined network slice is determined based on the acquired network slice information. If a determination that the base station does not provide the predetermined network slice is made, connection processing for connection between a communication apparatus and the base station is canceled, or connection between the communication apparatus and the base station is disconnected.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of co-pending U.S. patent applicationSer. No. 17/171,877 filed Feb. 9, 2021, which claims priority benefit ofJapanese Application No. 2020-022181 filed Feb. 13, 2020. Thedisclosures of the above-named applications are hereby incorporated byreference herein in their entireties.

BACKGROUND Field

The present disclosure relates to a communication apparatus thatcommunicates with a base station.

Description of the Related Art

The 3rd Generation Partnership Project (3GPP) standard specifies networkslicing as a mechanism for providing a communication service afterdesignating a network characteristic, such as a bandwidth or latency. Acommunication apparatus acquires information about a network slice to beprovided by a base station and performs connection processing duringRadio Resource Control (RRC) connection (Japanese Unexamined PatentApplication Publication (Translation of PCT Application) No.2019-533333).

However, there is a case where the base station cannot provide a desirednetwork slice. For example, in a case where the base station providesthe desired network slice to more than a predetermined number ofcommunication apparatuses, the base station can fail to provide thedesired network slice depending on the capacity of the base station or anetwork.

In such a case, if the communication apparatus maintains the connectionwith the base station, the communication apparatus unnecessarilyconsumes power for maintaining the connection with the base station,even though the communication apparatus cannot perform communicationusing the desired network slice.

SUMMARY

Various embodiments of the present disclosure describe enablingconnection control based on a network slice provided by a base station.

According to an embodiment of the present disclosure, a communicationapparatus includes an acquisition unit configured to acquire networkslice information indicating a characteristic of a wireless network tobe provided by a first base station, a determination unit configured todetermine whether the first base station provides a predeterminednetwork slice, based on the network slice information acquired by theacquisition unit, and a cancellation unit configured to cancelconnection processing for connection with the first base station in acase where the determination unit determines that the first base stationdoes not provide the predetermined network slice.

According to another embodiment of the present disclosure, acommunication apparatus includes an acquisition unit configured toacquire network slice information indicating a characteristic of awireless network to be provided by a first base station, a determinationunit configured to determine whether the first base station provides apredetermined network slice, based on the network slice informationacquired by the acquisition unit, and a disconnection unit configured todisconnect connection with the first base station, based on thedetermination unit determining that the first base station does notprovide the predetermined network slice.

Further features will become apparent from the following description ofexemplary embodiments with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a network configuration diagram according to one embodiment.

FIG. 2 is a table illustrating correspondence between slice servicetypes and slice service type values according to one embodiment.

FIG. 3 is a hardware configuration diagram of a communication apparatusaccording to one embodiment.

FIG. 4 is a software functional block diagram of the communicationapparatus according to one embodiment.

FIG. 5 is a flowchart of processing which is implemented by acommunication apparatus according to a first exemplary embodiment.

FIG. 6 is a flowchart of processing which is implemented by acommunication apparatus according to a second exemplary embodiment.

FIG. 7 is a table illustrating an unavailable base station listaccording to one embodiment.

FIG. 8 is a diagram illustrating an error message according to oneembodiment.

FIG. 9 is a flowchart of processing which is implemented by acommunication apparatus according to a third exemplary embodiment.

FIG. 10 is a flowchart of processing which is implemented by a basestation or a core network apparatus according to one embodiment.

FIG. 11 is a flowchart of processing which is implemented by acommunication apparatus according to a fourth exemplary embodiment.

DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments of the present disclosure will be described indetail below with reference to the attached drawings. Configurations tobe described in the following exemplary embodiments are only examples,and embodiments of the present invention are not limited to theillustrated configurations.

A communication apparatus according to a first exemplary embodiment willbe described in detail below with reference to drawings.

Communication apparatuses 101 and 102 in FIG. 1 each perform wirelesscommunication compliant with the 3rd Generation Partnership Project(3GPP) standard with a base station 105. A core network apparatus 106manages a core network formed by a plurality of base stations includingthe base station 105.

A network camera 103 is connected to the communication apparatus 101. Arobot arm 104 is connected to the communication apparatus 102. Theseconnections may be wired connections compliant with standards, such asEthernet and Universal Serial Bus (USB), or may be wireless connectionscompliant with standards, such as Institute of Electrical andElectronics Engineers (IEEE) 802.11 series and Bluetooth®.

When the network camera 103 uploads imaging data to a data server (notillustrated), the data is transmitted from the network camera 103 to thecommunication apparatus 101, from the communication apparatus 101 to thebase station 105, and from the base station 105 to the data server inthis order. When the robot arm 104 operates based on control data from aremote control server (not illustrated), the data is transmitted fromthe remote control server to the base station 105, from the base station105 to the communication apparatus 102, and from the communicationapparatus 102 to the robot arm 104 in this order.

The communication apparatus 101 connected to the network camera 103 usesa network slice with low latency to upload the imaging data captured bythe network camera 103 to the data server in real time. Thecommunication apparatus 102 connected to the robot arm 104 uses anetwork slice with high reliability to avoid a malfunction of the robotarm 104. The base station 105 provides the network slice with lowlatency and the network slice with high reliability. In other words, thenetwork slice indicates a characteristic (service) of a wireless networkto be provided by the base station 105. These characteristics areimplemented by controlling allocation of time slots and frequencyresources provided by the base station 105 (or the core networkapparatus 106) in the wireless network. Slice service type values of theabove-described network slices are shared by the core network side andthe communication apparatus side. FIG. 2 illustrates a list of the sliceservice type values in the present exemplary embodiment.

FIG. 3 illustrates a hardware configuration 301 of each of thecommunication apparatuses 101 and 102 of the present exemplaryembodiment. The hardware configuration 301 will be described below as aconfiguration of the communication apparatus 101. The communicationapparatus 102 has a similar hardware configuration.

A control unit 302 controls the entire communication apparatus 101 byexecuting a control program stored in a storage unit 303. The controlunit 302 includes one or more processors, such as a central processingunit (CPU) and a micro processing unit (MPU), and controls the entirecommunication apparatus 101 by executing a computer program stored inthe storage unit 303. The CPU and the MPU each function as a computer.The control unit 302 may control the entire communication apparatus 101based on cooperation between a program stored in the storage unit 303and an operating system (OS). The control unit 302 may include aplurality of processors, such as a multi-core processor, and control theentire communication apparatus 101 by using the plurality of processors.

The storage unit 303 stores the control program to be executed by thecontrol unit 302, and various types of information, such ascommunication parameters and captured-image data. The storage unit 303includes one or more memories, such as a read only memory (ROM) and arandom access memory (RAM), and stores a computer program for variousoperations (described below) and various types of information, such ascommunication parameters for wireless communication. For the storageunit 303, a storage medium, such as a flexible disk, a hard disk, anoptical disk, a magneto-optical (MO) disk, a compact disc ROM (CD-ROM),a CD-recordable (CD-R), a magnetic tape, a nonvolatile memory card, or adigital versatile disc (DVD) may be used other than the memories such asthe ROM and the RAM. The control unit 302 executes the control programstored in the storage unit 303, so that the various operations(described below 9 are performed.

A wireless communication unit 304 performs Long-Term Evolution (LTE) orfifth-generation (5G) cellular communication compliant with the 3GPPstandard. An output unit 305 is a display unit that performs varioustypes of display, and has the function of outputting visuallyrecognizable information, such as a liquid crystal display (LCD) or alight emitting diode (LED), or the function of outputting sound, such asa speaker. An input unit 306 receives various inputs from a user, oracquires sensor information.

FIG. 4 illustrates a software functional block diagram of each of thecommunication apparatuses 101 and 102 of the present exemplaryembodiment. The software functional blocks will be described below asthe blocks of the communication apparatus 101. The communicationapparatus 102 includes similar software functional blocks.

The control unit 302 of the communication apparatus 101 reads out aprogram stored in the storage unit 303 to implement the softwarefunctional blocks. At least some of the software functional blocksillustrated in FIG. 4 may be implemented by a hardware device. In thecase of the implementation by a hardware device, a dedicated circuit maybe generated on a field programmable gateway array (FPGA) from a programfor implementing each of the functional blocks by, for example, using apredetermined compiler, and the dedicated circuit may be used as ahardware module having the function of this software module. A gatearray circuit may be formed in a manner similar to the FPGA, so that thegate array circuit may be implemented as a hardware device.

A signal receiving unit 402 receives a signal compliant with the 3GPPstandard using the wireless communication unit 304, and a signaltransmission unit 403 transmits a signal compliant with the 3GPPstandard using the wireless communication unit 304. The communicationapparatus 101 thus performs LTE or 5G cellular network communicationcompliant with the 3GPP standard with another external apparatus. A datastorage unit 404 causes the storage unit 303 to hold software itself andinformation, such as authentication information.

A connection control unit 405 performs processing relating to connectionto and disconnection from a cellular network base station (e.g., thebase station 105) using the wireless communication unit 304. A displaycontrol unit 406 performs processing of controlling an image and soundto be output to the output unit 305. A Radio Resource Control (RRC)processing unit 407 performs RRC connection processing and cancellationprocessing using the wireless communication unit 304. A slice serviceinformation acquisition unit 408 acquires slice service informationnotified by the base station 105, using the wireless communication unit304.

A slice service information determination unit 409 determines whether aslice service provided by the base station 105 matches with or includesa slice service used by the communication apparatus 101, based on theslice service information notified by the base station 105.

FIG. 5 illustrates a flowchart of processing which is implemented by thecontrol unit 302 executing a program read out from the storage unit 303when the RRC connection is performed in the communication apparatus 101or 102. The communication apparatus 101 will be described below toimplement the processing. Similar processing is implemented by thecommunication apparatus 102 as well.

Some or all of steps in the flowchart illustrated in FIG. 5 may beimplemented by a hardware device, such as an application specificintegrated circuit (ASIC). The processing in the flowchart illustratedin FIG. 5 begins when the communication apparatus 101 transmits an RRCconnection request in response to a user operation of turning on thecommunication apparatus 101, a user operation of activating the wirelesscommunication unit 304, or a predetermined instruction from anapplication or an external apparatus (not illustrated). The RRCconnection request is a signal for requesting a base station toestablish RRC connection compliant with the 3GPP standard, and istransmitted to a base station compliant with the 3GPP standard.

First, in step S501, the communication apparatus 101 determines whetheran RRC Connection Setup message is received from the base station 105.If the RRC Connection Setup message is not received (NO in step S501),the communication apparatus 101 waits until the RRC Connection Setupmessage is received from the base station 105.

If the RRC Connection Setup message is received (YES in step S501), theprocessing proceeds to step S502. In step S502, the communicationapparatus 101 determines whether information about a network sliceprovided by the base station 105 is included in the received message.

If the information about the network slice is not included in the RRCConnection Setup message (NO in step S502), the processing proceeds tostep S503. In step S503, the communication apparatus 101 cancels the RRCconnection processing. The cancellation of the connection processing isimplemented by, for example, the communication apparatus 101 nottransmitting an RRC Connection Setup Complete message which is aresponse signal to the RRC Connection Setup message.

If the information about the network slice is included in the RRCConnection Setup message (YES in step S502), the processing proceeds tostep S504. In step S504, the communication apparatus 101 determineswhether the network slice indicated by the received slice informationmatches with a desired network slice.

For example, if “101” is included as a slice service type value in thereceived slice information and a slice service type value requested byan application running on the communication apparatus 101 is “101”, thecommunication apparatus 101 determines that the network slices matchwith each other. For example, if “101” is included as a slice servicetype value in the received slice information and a slice service typevalue requested by the network camera 103 connected to the communicationapparatus 101 is “101”, the communication apparatus 101 determines thatthe network slices match with each other. If “101” is not included as aslice service type value in the received slice information and a sliceservice type value requested by an application running on thecommunication apparatus 101 is “101”, the communication apparatus 101determines that the network slices do not match with each other.

If the network slice indicated by the received slice information doesnot match with the desired network slice (NO in step S504), theprocessing proceeds to step S503. In step S503, the communicationapparatus 101 cancels the RRC connection processing. If the networkslice indicated by the received slice information matches with thedesired network slice (YES in step S504), the processing proceeds tostep S505. In step S505, the communication apparatus 101 completes theRRC connection processing for connection with the base station 105.Specifically, the communication apparatus 101 transmits an RRCConnection Setup Complete message to the base station 105 to completethe RRC connection processing.

In this way, the network slice information indicating the characteristicof the wireless network to be provided by the base station 105 isacquired, and whether or not the base station 105 provides apredetermined network slice is determined based on the acquired networkslice information. If it is determined that the base station 105 doesnot provide the predetermined network slice, the connection processingfor connection with the base station 105 is canceled. The communicationapparatus 101 can be thus prevented from connecting to a base stationnot providing the desired network slice. Therefore, the communicationapparatus can obtain a power-saving effect, without consuming power formaintaining connection with the base station.

A second exemplary embodiment of the present disclosure will bedescribed below. In the second exemplary embodiment, a communicationapparatus manages base stations not providing a desired network slice,using a list. This list will be hereinafter referred to as theslice-unavailable base station list. FIG. 7 illustrates an example ofthe slice-unavailable base station list, and a pair of a base station ID(identifier) and an unavailability check date and time (timing at whichthe corresponding base station not providing a desired network slice ischecked) are included in the list.

While the following processing will be described as processing to beperformed by a communication apparatus 101, similar processing isperformed by a communication apparatus 102. A hardware configuration anda software configuration of the communication apparatus 101 are similarto those of the first exemplary embodiment and therefore will not bedescribed.

FIG. 6 illustrates a flowchart of processing to be implemented byexecution of a program read out from a storage unit 303 by a controlunit 302 when RRC connection is performed in the communication apparatus101. Some or all of steps in the flowchart illustrated in FIG. 6 may beimplemented by hardware such as an ASIC. The processing in the flowchartillustrated in FIG. 6 begins in a case where a user operation of turningon the communication apparatus 101 is performed, a user operation ofactivating a wireless communication unit 304 is performed, or apredetermined instruction is provided from an application or an externalapparatus (not illustrated). At the time when the flowchart illustratedin FIG. 6 begins, the slice-unavailable base station list is empty (nobase station information is included).

First, in step S601, the communication apparatus 101 checks whether abase station not in the slice-unavailable base station list is near thecommunication apparatus 101, i.e., within a communication range of thecommunication apparatus 101. The communication apparatus 101 performsthis check by receiving a broadcast signal from a base station, andcomparing the identification information (identifier) of the basestation included in the received broadcast signal and the identifier ofa base station included in the slice-unavailable base station list.

If the base station not in the slice-unavailable base station list isnot near the communication apparatus 101 (NO in step S601), theprocessing proceeds to step S602. In step S602, the communicationapparatus 101 notifies an error message, i.e., performs display or audiooutput of an error, or causes vibrations for notifying an error. Forexample, the communication apparatus 101 displays an error messageillustrated in FIG. 8 . Afterward, the processing illustrated in FIG. 6ends.

If the base station not in the slice-unavailable base station list isnot near the communication apparatus 101 (NO in step S601), theprocessing may repeat step S601, instead of proceeding to step S602. Inother words, the communication apparatus 101 may wait until the basestation not in the slice-unavailable base station list is detected.

If the base station not in the slice-unavailable base station list isnear the communication apparatus 101 (YES in step S601), the processingproceeds to step S603. In step S603, the communication apparatus 101selects the base station not in the slice-unavailable base station list,as a base station to be connected. In step S604, the communicationapparatus 101 transmits an RRC connection request to the selected basestation to be connected.

Next, in step S605, the communication apparatus 101 determines whetheran RRC Connection Setup message is received from the selected basestation to be connected. If the RRC Connection Setup message is notreceived (NO in step S605), the communication apparatus 101 waits untilthe RRC Connection Setup message is received from the base station.

If the RRC Connection Setup message is received (YES in step S605), theprocessing proceeds to step S606. In step S606, the communicationapparatus 101 determines whether information about a desired networkslice is included in the received message. This step is similar to stepS502 and step S504 in FIG. 5 . In other words, the communicationapparatus 101 determines that the information about the desired networkslice is included in the received message (YES in step S606), if aresult of the determination in step S502 is YES and a result of thedetermination in step S504 is YES. The communication apparatus 101determines that the information about the desired network slice is notincluded in the received message (NO in step S606), if a result of thedetermination in step S502 is NO or a result of the determination instep S504 is NO.

If the communication apparatus 101 determines that the information ofthe desired network slice is included in the received message (YES instep S606), the processing proceeds to step S607. In step S607, thecommunication apparatus 101 completes RRC connection processing. Thisstep is similar to step S505 in FIG. 5 .

If the communication apparatus 101 determines that the information aboutthe desired network slice is not included in the received message (NO instep S606), the processing proceeds to step S608. In step S608, thecommunication apparatus 101 adds this base station to theslice-unavailable base station list. More specifically, thecommunication apparatus 101 stores the identifier of this base stationand the date and time of the determination in step S606 in associationwith each other (as a pair) in the slice-unavailable base station list.In step S609, the communication apparatus 101 cancels the RRC connectionprocessing. This step is similar to step S503 in FIG. 5 . Afterward, theprocessing returns to step S601. The communication apparatus 101 canthus attempt to connect to another base station.

As described above, in a case where a network slice that can be providedby a base station to which the communication apparatus has attempted toconnect first is not a desired network slice, the communicationapparatus can attempt to connect to another base station, so that thepossibility of connecting to a base station providing the desirednetwork slice can be increased.

In place of or in addition to the date and time of the determination instep S606, the date and time of the addition to the slice-unavailablebase station list may be used as the information stored in theslice-unavailable base station list. In place of or in addition to this,the date and time when the communication apparatus 101 has canceled theRRC connection processing for connection with the base station may bestored.

The communication apparatus 101 may delete information about a basestation (information concerning a pair including this base station) fromthe slice-unavailable base station list, in a case where a predeterminedtime has elapsed since the date and time of the storage of this basestation in the slice-unavailable base station list. Thus, even if a basestation temporarily cannot provide a network slice requested by thecommunication apparatus 101, the communication apparatus 101 can attemptto connect to this base station when the base station is later enabledto provide the requested network slice. In other words, thecommunication apparatus 101 does not transmit an RRC connection requestto a base station included in the slice-unavailable base station list,only within a predetermined period. Therefore, the communicationapparatus can perform appropriate connection processing in response to achange, even in a case where the network slice providing status of thebase station dynamically changes.

Next, a third exemplary embodiment will be described. In the thirdexemplary embodiment, a communication apparatus adds information about anetwork slice desired by an external device to an RRC connectionrequest.

The following processing will be described as processing by acommunication apparatus 101, and similar processing is performed by acommunication apparatus 102. A hardware configuration and a softwareconfiguration of the communication apparatus 101 are similar to those inthe first exemplary embodiment and thus will not be described. A basestation 105 and a core network apparatus 106 each also have a hardwareconfiguration similar to that in FIG. 3 . The communication apparatus101 operates as a relay apparatus that relays communication between theexternal device and the base station 105.

FIG. 9 illustrates a flowchart of processing to be implemented by acontrol unit 302 executing a program read out from a storage unit 303when RRC connection is performed in the communication apparatus 101.Some or all of steps in the flowchart illustrated in FIG. 9 may beimplemented by a hardware device, such as an ASIC. The processing in theflowchart illustrated in FIG. 9 begins in a case where a user operationof turning on the communication apparatus 101 is performed, a useroperation of activating a wireless communication unit 304 is performed,or a predetermined instruction is provided from an application or anexternal apparatus (not illustrated).

First, in step S1001, the communication apparatus 101 determines whetherthe communication apparatus 101 is connected to an external device. Ifthe communication apparatus 101 is not connected to an external device(NO in step S1001), the processing proceeds to step S1002. In stepS1002, the communication apparatus 101 transmits an RRC connectionrequest to the base station 105 without setting a slice service typevalue, i.e., without including information about a requested networkslice therein.

If the communication apparatus 101 is connected to an external device(YES in step S1001), the processing proceeds to step S1003. In stepS1003, the communication apparatus 101 determines whether the connectedexternal device is a network camera. If the connected external device isthe network camera (YES in step S1003), the processing proceeds to stepS1004. In step S1004, the communication apparatus 101 sets “101” as aslice service type value and transmits an RRC connection request to thebase station 105. In other words, the communication apparatus 101 addsinformation indicating that a low latency slice service is requested tothe RRC connection request, and transmits the RRC connection request tothe base station 105.

If the communication apparatus 101 determines that the connectedexternal device is not the network camera (NO in step S1003), theprocessing proceeds to step S1005. In step S1005, the communicationapparatus 101 determines whether the connected external device is arobot arm. If the connected external device is not the robot arm (NO instep S1005), the processing proceeds to step S1002. In step S1002, thecommunication apparatus 101 transmits an RRC connection request to thebase station 105 without setting a slice service type value, i.e.,without including information about the requested network slice therein.

If the connected external device is the robot arm (YES in step S1005),the processing proceeds to step S1006. In step S1006, the communicationapparatus 101 sets “102” to a slice service type value and transmits anRRC connection request to the base station 105. In other words, thecommunication apparatus 101 adds information indicating that a highreliability slice service is requested to the RRC connection request andtransmits the RRC connection request to the base station 105.

In the flowchart in FIG. 9 , the information about the network slicerequested by the external device is added. However, in place of or inaddition to this, information about a network slice requested by thecommunication apparatus 101 may be added to the RRC connection request.Here, the network slice requested by the communication apparatus 101 maybe a network slice set beforehand as the communication apparatus 101 orset by a user, or may be a network slice requested by an applicationrunning on the communication apparatus 101.

FIG. 10 illustrates a flowchart of processing implemented by the basestation 105 in a case where the base station 105 receives an RRCconnection request to which information about a requested network sliceis added from the communication apparatus 101. The processing in thisflowchart is implemented by a control unit executing a program read outfrom a storage unit. While the processing illustrated in FIG. 10 will bedescribed below to be performed by the base station 105, the basestation 105 may transfer the RRC connection request received from thecommunication apparatus 101 to the core network apparatus 106, and thecore network apparatus 106 may implement the processing illustrated inFIG. 10 .

First, in step S1101, the base station 105 determines whether the numberof other communication apparatuses using the same network slice as thenetwork slice requested by the communication apparatus 101 is less thanor equal to a predetermined number (e.g., ten). If the number of othercommunication apparatuses is less than or equal to the predeterminednumber (YES in step S1101), the processing proceeds to step S1102. Instep S1102, the base station 105 transmits an RRC Connection Setupmessage to which information about the requested network slice is addedto the communication apparatus 101, as a response to the RRC connectionrequest. If the number of other communication apparatuses is more thanthe predetermined number (NO in step S1101), the processing proceeds tostep S1103. In step S1103, the base station 105 transmits an RRCConnection Setup message to which the information about the requestednetwork slice is not added to the communication apparatus 101, as aresponse to the RRC connection request.

In this way, the base station 105 can notify the communication apparatus101 of whether the requested network slice is available, based on thenumber of other communication apparatuses that are using the requestednetwork slice.

In step S1101, the base station 105 may perform the determination basedon the total communication data amount of one or more othercommunication apparatuses that are using the network slice, in place ofthe number of other communication apparatuses that are using the networkslice. In this case, if the total communication data amount of one ormore other communication apparatuses that are using the network slice ismore than or equal to a predetermined threshold, the processing proceedsto step S1103. Here, the total communication data amount indicates atotal communication data amount that the other communication apparatuseshave communicated with the base station 105 within a predeterminedperiod. If the total communication data amount is less than thethreshold, the processing proceeds to step S1102. The base station 105can thus notify whether the requested network slice is available, basedon the total communication data amount.

Which criterion for the determination is to be used may be settable by auser in the base station 105. The base station 105 can thus notifywhether the requested network slice is available, using the criterionintended by the user (e.g., an administrator in a local 5G system).

Except for the addition of the information about the network slicedesired by the external device to the RRC connection request, thecommunication apparatus 101 performs processing similar to that of thefirst exemplary embodiment (FIG. 5 ) or the second exemplary embodiment(FIG. 6 ). However, instead of this, step S504 may be omitted and theprocessing may proceed to step S505 if a result of the determination instep S502 is YES, in the first exemplary embodiment (FIG. 5 ). In thesecond exemplary embodiment (FIG. 6 ), only the operation correspondingto step S502 may be performed as step S605 (i.e., the operationcorresponding to step S504 is omitted). This can reduce the processingload of the communication apparatus 101.

As described above, the communication apparatus can request the basestation to provide an appropriate network slice depending on theexternal device, in the RRC connection. In a case where informationabout a network slice desired by the communication apparatus 101 inplace of or in addition to the external device is added, thecommunication apparatus 101 can request the base station to provide thenetwork slice desired by the communication apparatus 101, in the RRCconnection.

In a fourth exemplary embodiment, there will be described a case whereRRC connection is disconnected after RRC connection processing iscompleted once instead of being canceled by a communication apparatus.While the following processing will be described as processing to beperformed by a communication apparatus 101, similar processing isperformed by a communication apparatus 102. A hardware configuration anda software configuration of the communication apparatus 101 are similarto those of the first exemplary embodiment and thus will not bedescribed.

FIG. 11 illustrates a flowchart of processing which is implemented by acontrol unit 302 executing a program read out from a storage unit 303when RRC connection is performed in the communication apparatus 101.Some or all of the steps in the flowchart illustrated in FIG. 11 may beimplemented by a hardware device, such as an ASIC. The processing in theflowchart illustrated in FIG. 11 begins when the communication apparatus101 transmits an RRC connection request in response to a user operationof turning on the communication apparatus 101, a user operation ofactivating a wireless communication unit 304, or a predeterminedinstruction from an application or an external apparatus (notillustrated). Operations similar to those in steps in FIG. 5 areprovided with the same reference numerals as those in FIG. 5 and willnot be specifically described.

In the processing in FIG. 11 as well, the communication apparatus 101receives an RRC Connection Setup message from a base station 105 (YES instep S501). If information about a desired network slice is not includedin the RRC Connection Setup message (NO in step S502 or NO in stepS504), the processing proceeds to step S1201. The operation in stepS1201 is similar to the operation in step S505. In other words, in stepS1201, the communication apparatus 101 completes the RRC connectionprocessing for connection with the base station 105. Subsequently, instep S1202, the communication apparatus 101 disconnects the RRCconnection with the base station 105. More specifically, initially, thecontrol unit 302 of the communication apparatus 101 issues an AttentionHang-up the current call (ATH) command for disconnecting the RRCconnection to the wireless communication unit 304. The ATH command isone of Attention (AT) commands that is a command for controlling amodem. In response to receiving the ATH command, the wirelesscommunication unit 304 transmits an RRC disconnection request to thebase station 105, thus disconnecting the RRC connection. Here, the RRCdisconnection request is a “REQUEST PDP CONTEXT ACTIVATION REJECT”message or a “DEACTIVATE PDP CONTEXT REQUEST” message compliant with the3GPP standard. The term “PDP” is an abbreviation of Packet DataProtocol. These messages are intended to deactivate a PDP context, andthe RRC connection is disconnected as a result.

In step S1203, the communication apparatus 101 notifies a user that theRRC connection is disconnected. Here, this notification is performed bydisplay or audio output, or causing vibrations. Thus, in a case wherethe desired network slice is not available, the RRC connection isdisconnected, and the user can recognize that the RRC connection isdisconnected.

In the processing in FIG. 11 , the communication apparatus 101 mayperform operation equivalent to the operation in step S505, i.e., maycomplete the RRC connection processing, if a result of the determinationin step S501 is YES. Subsequently, the determination in each of stepS502 and S504 is performed. In this case, the RRC connection processing(step S505 and step S1201) after the determination in each of step S502and S504 is omitted. A similar operational effect can also be obtainedby such an operation.

A storage medium storing a program code of software that implements theabove-described function may be supplied to a system or apparatus, and acomputer (a CPU or MPU) of the system or apparatus may read out theprogram code stored in the storage medium and execute the read-outprogram code. In this case, the program code read out from the storagemedium implements the above-described function of the exemplaryembodiment, and the storage medium storing the program code is includedin the above-described apparatus.

Usable examples of the storage medium for supplying the program codeinclude a flexible disk, a hard disk, an optical disk, an MO disk, aCD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM, and aDVD.

The above-described function may be implemented not only by theexecution of the program code read out by the computer, but also byexecution of a part or all of actual processing by an OS running on thecomputer based on an instruction of the program code.

Further, the above-described function may be implemented as follows.First, the program code read out from the storage medium is written intoa memory included in an expansion board inserted into the computer or anexpansion unit connected to the computer. Subsequently, based on aninstruction of the program code, a CPU included in the expansion boardor the expansion unit performs a part or all of the actual processing toimplement the above-described function.

Various embodiments of the present disclosure can also be implemented bysupplying a program that implements one or more functions of each of theabove-described exemplary embodiments to a system or apparatus via anetwork or storage medium, and causing one or more processors in acomputer of the system or apparatus to read out the program and executethe read-out program. Embodiments of the present disclosure can also beimplemented by a circuit (e.g., an ASIC) for implementing the one ormore functions.

While embodiments of the present disclosure have been described withreference to exemplary embodiments, it is to be understood that theinvention is not limited to the disclosed exemplary embodiments. Thescope of the following claims is to be accorded the broadestinterpretation so as to encompass all such modifications and equivalentstructures and functions.

1. A communication apparatus comprising: at least one memory that storesa set of instructions; and at least one processor that executes theinstructions, the instructions, when executed, causing the communicationapparatus to perform operations comprising: acquiring network sliceinformation indicating a characteristic of a wireless network to beprovided by a base station before establishing a connection with thebase station; and determining whether to connect to the base stationbased on the acquired network slice information.
 2. The communicationapparatus according to claim 1, wherein the operations further comprisedetermining, before establishing a connection with the base station,whether a predetermined network slice is to be provided if theconnection with the base station is established, based on the acquirednetwork slice information.
 3. The communication apparatus according toclaim 2, wherein the operations further comprise controlling, in a casewhere it is determined that, if the connection with the base station isestablished, the predetermined network slice is to be provided, controlto connect to the base station is performed, and in a case where it isdetermined that, if the connection with the base station is established,the predetermined network slice is not to be provided, control so as notto connect to the base station is performed.
 4. The communicationapparatus according to claim 1, wherein the operations further comprisedetecting other base stations near the communication apparatus.
 5. Thecommunication apparatus according to claim 1, wherein the operationsfurther comprise: identifying a type of network slice to be used for anapplication being executed, and controlling a process of determiningwhether to connect to the base station is performed based on theacquired network slice information and the identified type, and controlto connect to the base station or control so as not to connect to thebase station is performed based on a result of the process of thedetermining.
 6. The communication apparatus according to claim 1,wherein the communication apparatus having been connected to the basestation performs a wireless communication compliant with a communicationstandard specified by the 3rd Generation Partnership Project, with thebase station.
 7. The communication apparatus according to claim 6,wherein the wireless communication is a cellular communication compliantwith the fifth-generation technology standard.
 8. The communicationapparatus according to claim 1, wherein the communication apparatus iswired to a functional module, and wherein the operations furthercomprise receiving or transmitting data for the functional module viathe wired communication.
 9. The communication apparatus according toclaim 8, wherein the functional module is a camera, and wherein theoperations further comprise transmitting, in a case where a connectionwith the base station is established, imaging data which is obtainedfrom the camera to the base station.
 10. A communication methodcomprising: acquiring network slice information indicating acharacteristic of a wireless network to be provided by a base stationbefore establishing a connection with the base station; and determiningwhether to connect to the base station based on the acquired networkslice information.
 11. A non-transitory computer-readable storage mediumthat stores a program for causing a communication apparatus to execute:acquiring network slice information indicating a characteristic of awireless network to be provided by a base station before establishing aconnection with the base station; and determining whether to connect tothe base station based on the acquired network slice information.